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Related papers: Dissipation Enhancement by Mixing

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We study diffusion and mixing in different linear fluid dynamics models, mainly related to incompressible flows. In this setting, mixing is a purely advective effect which causes a transfer of energy to high frequencies. When diffusion is…

Analysis of PDEs · Mathematics 2018-06-11 Michele Coti Zelati , Matias G. Delgadino , Tarek M. Elgindi

Motivated by mixing processes in analytical laboratories, this work investigates enhanced dissipation in non-autonomous flows. We study the evolution of concentrations governed by the advection-diffusion equation, where the velocity field…

Analysis of PDEs · Mathematics 2025-09-04 Johannes Benthaus , Camilla Nobili

This work deals with mixing and dissipation ehancement for the solution of advection-diffusion equation driven by a Ornstein-Uhlenbeck velocity field. We are able to prove a quantitative mixing result, uniform in the diffusion parameter,…

Probability · Mathematics 2022-09-16 Umberto Pappalettera

An upper bound on the mixing efficiency is derived for a passive scalar under the influence of advection and diffusion with a body source. For a given stirring velocity field, the mixing efficiency is measured in terms of an equivalent…

Fluid Dynamics · Physics 2007-12-12 Jean-Luc Thiffeault , Charles R. Doering , John D. Gibbon

Recent experimental results indicate that mixing is enhanced by a reciprocal flow induced inside a levitated droplet with an oscillatory deformation [T. Watanabe et al. Sci. Rep. 8, 10221 (2018)]. Generally, reciprocal flow cannot convect…

Motivated in part by the work of Vanneste and Byatt-Smith, we study mixing and enhanced dissipation for the advection-diffusion equation with velocity field $\mathbf{u}(x,y,t)=(\sin(y-ct),0)$, a shear flow whose profile translates rigidly…

Analysis of PDEs · Mathematics 2026-03-17 Johannes Benthaus , Giuseppe Maria Coclite , Camilla Nobili

We present several numerical results on granular mixtures. In particular, we examine the efficiency of diffusion as a mixing mechanism in these systems. The collisions are inelastic and to compensate the energy loss, we thermalize the…

Statistical Mechanics · Physics 2009-10-31 C. Henrique , G. Batrouni , D. Bideau

We consider the advection-diffusion equation on $\mathbb{T}^2$ with a Lipschitz and time-periodic velocity field that alternates between two piecewise linear shear flows. We prove enhanced dissipation on the timescale $|\log \nu|$, where…

Analysis of PDEs · Mathematics 2023-04-12 Tarek M. Elgindi , Kyle Liss , Jonathan C. Mattingly

We consider absorbing chemical reactions in a fluid flow modeled by the coupled advection-reaction-diffusion equations. In these systems, the interplay between chemical diffusion and fluid transportation causes the enhanced dissipation…

Analysis of PDEs · Mathematics 2022-07-27 Siming He , Alexander Kiselev

We consider the effect of noise on the dynamics generated by volume-preserving maps on a d-dimensional torus. The quantity we use to measure the irreversibility of the dynamics is the dissipation time. We focus on the asymptotic behaviour…

Dynamical Systems · Mathematics 2009-11-10 A. Fannjiang , S. Nonnenmacher , L. Wolowski

Discrete element method simulations of confined bidisperse granular shear flows elucidate the balance between diffusion and segregation that can lead to either mixed or segregated states, depending on confining pressure. Results indicate…

Soft Condensed Matter · Physics 2018-09-24 Alexander M. Fry , Paul B. Umbanhowar , Julio M. Ottino , Richard M. Lueptow

In this paper, we introduce a diffuse interface model for describing the dynamics of mixtures involving multiple (two or more) phases. The coupled hydrodynamical system is derived through an energetic variational approach. The total energy…

Analysis of PDEs · Mathematics 2014-02-24 J. Brannick , C. Liu , T. Qian , H. Sun

We study the contribution of advection by thermal velocity fluctuations to the effective diffusion coefficient in a mixture of two identical fluids. The steady-state diffusive flux in a finite system subject to a concentration gradient is…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 A. Donev , A. de la Fuente , J. B. Bell , A. L. Garcia

We study a system consisting of a particle adsorbed on a carbon nanotube resonator. The particle is allowed to diffuse along the resonator, in order to enable study of e.g. room temperature mass sensing devices. The system is initialized in…

Mesoscale and Nanoscale Physics · Physics 2014-10-17 Christin Edblom , Andreas Isacsson

We study passive scalar mixing by parallel shear flows in the presence of weak molecular diffusion. We recover the sharp uniform-in-diffusivity mixing rate for shear flows with finitely many critical points, recently proven in [1]. Our…

Analysis of PDEs · Mathematics 2026-03-11 Kyle L. Liss , Kunhui Luan

We study the dissipation enhancement by cellular flows. Previous work by Iyer, Xu, and Zlato\v{s} produces a family of cellular flows that can enhance dissipation by an arbitrarily large amount. We improve this result by providing…

Analysis of PDEs · Mathematics 2024-03-12 Gautam Iyer , Hongyi Zhou

Evidence suggests that the transport rate of a passive particle at long timescales is enhanced due to interactions with the surrounding active ones in a size- and composition-dependent manner. Using a system of particles with different…

Soft Condensed Matter · Physics 2021-07-14 Efe Ilker , Michele Castellana , Jean-François Joanny

In many situations, the combined effect of advection and diffusion greatly increases the rate of convergence to equilibrium -- a phenomenon known as enhanced dissipation. Here we study the situation where the advecting velocity field…

Dynamical Systems · Mathematics 2025-02-11 William Cooperman , Gautam Iyer , Seungjae Son

Advection-diffusion coupling can enhance particle and solute dispersion by orders of magnitude as compared to pure diffusion, with a steady state being reached for confined flow regions such as a nanopore or blood vessel. Here, by using…

We study the interface dynamics of a binary particle mixture in a rotating cylinder numerically. By considering only the particle motion in axial direction, it is shown that the initial dynamics can be well described by a one-dimensional…

Soft Condensed Matter · Physics 2007-05-23 Christian M. Dury , Gerald H. Ristow
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